Hollow body cavity ablation apparatus

ABSTRACT

An ablation apparatus places electrodes at the perimeter of a cavity. In an embodiment, the alternating electric field is used to expose the cavity to enough energy to ablate the cavity. In an embodiment, two modes are used to expose different regions of the cavity to different amounts of power for so that the thermal effect is more uniform. In an embodiment, the electrodes have a relatively large surface area so as to avoid charring the cavity, but are shaped so as to fit within a body orifice. For example, the diameter of the sheathed housing the electrodes during penetration may be only 5.5 mm.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority benefit of U.S. Provisional PatentApplication No. 61/259,973, entitled “Hollow Body Cavity AblationApparatus,” filed Nov. 10, 2009, which is incorporated herein byreference.

FIELD

This specification generally relates to embodiments of hollow bodyablation devices and uses thereof.

BACKGROUND

The subject matter discussed in the background section should not beassumed to be prior art merely as a result of its mention in thebackground section. Similarly, a problem mentioned in the backgroundsection or associated with the subject matter of the background sectionshould not be assumed to have been previously recognized in the priorart. The subject matter in the background section merely representsdifferent approaches, which in and of themselves may also be inventions.

Ablation of the interior lining of a body organ is a procedure thatinvolves heating the organ lining to temperatures that destroys thecells of the lining and coagulates blood flow for hemostasis. Such aprocedure may be performed as a treatment to one of many conditions,such as chronic bleeding of the endometrial layer of the uterus orabnormalities of the mucosal layer of the gallbladder. Existing methodsfor effecting ablation include circulation of a heated fluid inside theorgan (either directly or inside a balloon) and laser treatment of theorgan lining. New methods and devices may be desirable for effectinghollow body cavity ablation.

SUMMARY

Methods and devices are provided for effecting hollow body cavityablation. The devices are adjustable to fit the perimeter of a varietyof organ sizes and to fold into a small size for insertion into a smallopening.

Any of the above embodiments may be used alone or together with oneanother in any combination. Inventions encompassed within thisspecification may also include embodiments that are only partiallymentioned or alluded to or are not mentioned or alluded to at all inthis brief summary or in the abstract.

BRIEF DESCRIPTION OF THE FIGURES

In the following drawings like reference numbers are used to refer tolike elements. Although the following figures depict various examples ofthe invention, the invention is not limited to the examples depicted inthe figures.

FIG. 1A shows a front elevation view of an embodiment of a hollow bodyablation device attached to a controller system and a fluid removaldevice.

FIG. 1B shows a screen shot of one screen of a user interface of thecontroller system.

FIG. 1C shows a screen shot of another screen of a user interface of thecontroller system.

FIG. 1D shows a drawing of an embodiment of electrode activation for anembodiment of a hollow body ablation device having 6 electrodes and twomodes.

FIG. 2 shows an embodiment of a controller system for a hollow bodyablation apparatus.

FIGS. 3A-C show front elevation views of three more embodiments ofhollow body ablation devices. FIG. 3B is a partial cutaway view of anembodiment of a hollow body ablation device.

FIG. 4 shows a front elevation view of an embodiment of a hollow bodyablation device using extension spring or coil electrodes and pushwires.

FIG. 5 shows a front elevation view of an embodiment of a hollow bodyablation device using telescoping electrodes.

FIG. 6A shows a front elevation view of the inside of an embodiment ofthe handpiece.

FIG. 6B shows a cross sectional view of an embodiment of the inside ofhandpiece FIG. 6A.

FIG. 6C shows a blowup of a portion of FIG. 6B.

FIG. 7 shows a front elevation view of an embodiments of the outside ofthe handpiece on FIG. 6A, including length and width adjustments.

FIG. 8A shows an embodiment of a fluid removal device.

FIG. 8B shows another view of the fluid removal device.

FIG. 9 shows a flowchart of a method of using an embodiment of a hollowbody ablation device.

FIG. 10 shows a flowchart of a method of assembling the systemcomponents of an embodiment of a hollow body ablation apparatus.

FIG. 11 shows a flowchart of a method of assembling the systemcomponents of the hollow body ablation device.

FIG. 12 shows a front elevation view of a method of testing a hollowbody ablation apparatus-post-treatment.

FIG. 13 shows a front elevation view of a method of testing a hollowbody ablation apparatus-post-treatment.

FIGS. 14 and 15 show side elevations of the ablated test material.

FIGS. 16 and 17 show Tables 2A and 2B, which show test results of theablation.

DETAILED DESCRIPTION

Although various embodiments of the invention may have been motivated byvarious deficiencies with the prior art, which may be discussed oralluded to in one or more places in the specification, the embodimentsof the invention do not necessarily address any of these deficiencies.In other words, different embodiments of the invention may addressdifferent deficiencies that may be discussed in the specification. Someembodiments may only partially address some deficiencies or just onedeficiency that may be discussed in the specification, and someembodiments may not address any of these deficiencies.

In general, at the beginning of the discussion of each of FIGS. 1A-8 isa brief description of each element, which may have no more than thename of each of the elements in the one of FIGS. 1A-8 that is beingdiscussed. After the brief description of each element, each element isfurther discussed in numerical order. In general, each of FIGS. 1-17 isdiscussed in numerical order and the elements within FIGS. 1-17 are alsousually discussed in numerical order to facilitate easily locating thediscussion of a particular element. Nonetheless, there is no onelocation where all of the information of any element of FIGS. 1A-17 isnecessarily located. Unique information about any particular element orany other aspect of any of FIGS. 1A-17 may be found in, or implied by,any part of the specification.

In various places in discussing the drawings a range of letters, such as“a-z” are used to refer to individual elements of various series ofelements that are the same. In each of these series, the ending lettersare integer variables that can be any number. Unless indicatedotherwise, the number of elements in each of these series is unrelatedto the number of elements in others of these series. Specifically, eventhough one letter (e.g. “a”) comes earlier in the alphabet than anotherletter (e.g., “e”), the order of these letters in the alphabet does notmean that the earlier letter represents a smaller number. The value ofthe earlier letter is unrelated to the later letter, and may represent avalue that is greater the same or less than the later letter.

FIG. 1 shows an overhead view of an embodiment of a hollow body ablationapparatus used in methods of ablation of hollow body organs. Theablation apparatus 100 may include a handheld implement 101, a powersupply 102, a controller system (a controller) 104 and an aspiratordevice 103. The handheld implement 101 may include a head 110, areservoir 113, a connector 150, an aspiration port 140, a sheath 130, anaspiration tube 133, one or more insulators 120, 121, and 122, one ormore electrodes 160 a-z, a handpiece 180, a length adjustment 182, awidth adjustment 184 for deploying the device. Ablation apparatus 100may also include foot control 186. In other embodiments the ablationapparatus 100 and/or handheld implement 101 may not have all of theelements or features listed and/or may have other elements or featuresinstead of or in addition to those listed.

In this application the term “perimeter” when used in reference to theuterus refers to outside of the ablation region or endometrium. Theablation apparatus 100 is an example of a system that can be used forablation of the interior lining of a body organ that may be hollow. Theablation apparatus 100 may include electrodes that can be arranged in apattern that makes contact with the surface area of the cavity of thehollow body organ in close proximity to the perimeter. Energizing theelectrodes can result in a complete or partial ablation of the lining ofthe body cavity without the necessity of moving the electrodes, eventhough the electrodes only make contact with the surface area of theorgan in proximity to the perimeter. The user of ablation apparatus 100may be anyone who uses the ablation apparatus 100 during a hollow bodyablation procedure. Users may include doctors, surgeons, nurses,veterinarians, and any support staff that might be helping with aprocedure, for example. The procedure may be done in an operating roomor as an outpatient procedure, for example.

The handheld implement 101 can be used for ablation of a hollow cavitywith anterior and posterior surfaces while the anterior and posteriorsurfaces are either separated or contacting one another. The handheldimplement 101 may include a head 110, which may have any shape,according to the cavity that is intended to be ablated, and/or can beadjusted to approximate the perimeter of a hollow body organ. Thehandheld implement 101 can have electrodes arranged in a pattern thatallow for placement in the perimeter of the hollow body organ. Thehandheld implement 101 has controls (e.g., on the handheld implement101) that allow the user to reduce the overall profile and size of thehandheld implement 101 to allow for minimally invasive access, to beable to better conform to organs with distorted cavity shapes. Thehandheld implement 101 has the advantage that handheld implement 101 isable to collapse on itself to form a small tube that will fit into asmall diameter aperture. In some embodiments, the aperture has adiameter between about 4 and about 7 mm, including but not limited to4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8, 4.9, 5.0, 5.1, 5.2, 5.3, 5.4,5.5, 5.6, 5.7, 5.8, 5.9, 6.0, 6.1, 6.2, 6.3, 6.4, 6.5, 6.6, 6.7, 6.8,and 6.9 mm. In the case where the diameter is between 4 and 7 mm, thehandheld implement 101 can collapse upon itself until handheld implement101 has a diameter of between about 4 or 5.5 and about 7 mm, includingbut not limited to 4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8, 4.9, 5.0,5.1, 5.2, 5.3, 5.4, 5.5, 5.6, 5.7, 5.8, 5.9, 6.0, 6.1, 6.2, 6.3, 6.4,6.5, 6.6, 6.7, 6.8, and 6.9 mm. In some embodiments, the diameter of theaperture is about 5.5 mm and the diameter of the handheld implement 101when collapsed is less than 5.5 mm, which is smaller than the diameterof heads of prior art ablation devices.

The handheld implement 101 in the invention can have various geometricadjustments applied through operating controls on the handpiece 180 ofthe handheld implement 101 that change the size and/or shape of head.

The power supply 102 may include a transformer for converting thevoltage and/or an alternating current source, such as a variableoscillator, which may generate Radio Frequency (RF) Alternating Current(AC). Alternatively, power supply 102 may include a generator. The powersupply 102 controls the frequency of the alternating current that isoutput by power supply 102.

The aspiration device 103 includes an aspiration tube 133 and areservoir 113 and may act to remove excess fluid, (i.e. liquid, vaporand gases), from the hollow body organ before, during and/or after theprocess of ablation (e.g., the procedure) (it is not necessary to removeall fluids from the cavity). The aspirator device 103 can use any methodof fluid removal, including a pump, suction, and/or aspirator to removethe fluids.

The controller 104 may include an algorithm that allows for the controlof the alternating current (AC). The power supply 102 may be a part ofthe controller 104 or separate from the controller 104. The controller104 may be capable of applying different patterns of alternating thepolarities of the different electrodes of ablation apparatus 100,changing electrode polarities in various combinations to effect bipolarablation between selected electrodes or monopolar ablation to a neutralelectrode. The frequency, voltage, and/or current may be adjusted to fitthe cavity dimensions to limit the ablation effects to the desiredtissue or tissue layers, and minimize collateral effects, and can beused to determine overall therapeutic energy doses, and/or determineother settings such as power, duration (the amount of time) ofapplication of the electric field, etc. See FIG. 1D for a diagram ofelectrode bipolar coupling pairs and FIGS. 16 and 17 for the energydelivery algorithms that can be used.

The power supply 102 and controller 104 are capable of driving multipleelectrodes in various bipolar pairs located in the handheld implement101 and in proximity to the perimeter of the hollow organ, so as toautomatically sequence through a desired set of bipolar or monopolarablation polarities and/or algorithms. The controller 104 is discussedin more detail in conjunction with reference to FIG. 2.

In some embodiments, the head 110 is a generally triangular handheldimplement 101 having an approximately isosceles triangular shape. Thearea distal to the handpiece 180 is the base. However, even when thehead 110 is a parallelogram shape, the base can still be thought of asthe side distal to the handpiece 180. If the head 110 has a morecircular or oval shape, the base can be thought of as the area mostdistal to the handpiece 180. Upon full opening of the head 110, the basecan be between about 2 and about 4.5 cm and the length upon full openingof the head 110 between about 4 and about 6.5 cm. Other embodiments ofthis device can have generally larger or smaller base width and lengthranges, depending on the size of the organ being ablated. The termgenerally triangular, means that the handheld implement 101 can be anyshape, such as a generally triangular shape (including a roundedtriangle), a square, a parallelogram, a circle, ellipse, rhombus,spiral, etc. but, in the case of the square, parallelogram, circle orellipse, the “base” is the side most distal from the handpiece and the“sides” are the pieces on either side of the “base.” The shape maydepend in part on how far apart the sides are in the sheath 130 and/orhandpiece 180. In some embodiments, the base is the most distal sidefrom the handheld implement 101 and upon full opening of the handheldimplement 101, the base can be between about 1.5 or 2 and about 5 cm,including but not limited to 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8,2.9, 3.0, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4.0, 4.1, 4.2,4.3, 4.4, 4.5, 4.6, 4.7, 4.8, and 4.9 cm. In some embodiments, the sidesof the device are between about 3.5 and about 7 cm, including, but notlimited to, 3.6, 3.7, 3.8, 3.9, 4.0, 4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7,4.8, 4.9, 5.0, 5.1, 5.2, 5.3, 5.4, 5.5, 5.6, 5.7, 5.8, 5.9, 6.0, 6.1,6.2, 6.3, 6.4, 6.5, 6.6, 6.7, 6.8, and 6.9 cm.

The reservoir 113 may be a part of aspirator device 103, and may be anytype of reservoir that may contain body fluids (i.e. liquids, vapors orgases) without spreading biohazards. In some embodiments. The pump, 214in FIG. 2, can be any pump. In some embodiments, the pump is amechanical pump, a finger pump, a syringe pump, vacuum canister, turbinepump, peristaltic pump or other method for creating a negative pressure.Alternatively, the system can be connected to wall vacuum that exists inthe hospital or surgical suite.

In the embodiment shown in FIG. 1A, there are multiple insulators 120,121, and 122 that function to keep the electrodes 160 a-z from touchingand possibly shorting out. The electrode shells may be continuous, orslotted on one or more sides or in a generally spiral pattern tofacilitate bending and adaptation to the organ perimeter. The sideinsulators 120, 121 and 122 walls may be continuous, or slotted on oneor more sides or in a generally spiral pattern to facilitate bending andadaptation to the organ perimeter. The electrode cross sections may beof any geometry, including circular, elliptical, rectangular, or nonsymmetric ‘D’ shaped which may be preferable for maximizing electrodesurface area for contact with the organ wall for a device which must beintroduced through a small diameter aperture. Similarly, the crosssections of the side insulators 120, 121, and 122 in FIG. 1A may be ofany geometry, including circular, elliptical, rectangular, or nonsymmetric ‘D’ shaped. The insulator cross sections may match that of theelectrodes so that if, for example the electrode cross sections are ‘D’shaped and slotted, the insulators 120, 121 and 122 are D-shaped andfunction to separate the slotted D-tube electrodes 161 from the D-tubeelectrodes 162. The side insulators 120, 121, and 122 may also be hollowto allow push/pull wires and/or signal wires and conduits or tubes to beinserted through. The side insulators 120, 121, and 122 can beconstructed of Polyether Ether Ketone (PEEK) or any other,non-conductive insulator material. The melting temperature of sideinsulators 120, 121, and 122 should be high enough so as not to meltduring ablation (e.g., it may be desirable that the melting temperatureof the insulator be higher than 400 degrees Fahrenheit).

In the embodiment shown in FIG. 1A, there are corner insulators 121 a-zthat can be rigid D-shaped insulators and function to separate D-tubeelectrodes 162 from coil electrodes 163. The corner insulators 121 a-zcan be constructed of polyimide or any other non-conductive insulator.

In the embodiment shown in FIG. 1A, there is a distal insulator 122 thatcan be constructed of a strip of non-conductive material. The distalinsulator 122 functions to separate the coil electrodes 163 and to givethe electrodes 163 single plane flexibility. The distal insulator 122can also be highly flexible to fold to allow the two base electrodes 163to fold up themselves when the head 110 is collapsed and inserted intothe sheath 130.

The handheld implement 101 can have various geometric adjustmentsapplied through operating controls on the handpiece 180 of the handheldimplement 101. The operating controls may allow for adjusting theelectrodes 160 a-z to fit the perimeter of organs of various sizes andshapes. For a triangular shaped hollow organ cavity such as the humanfemale uterus, the adjustments can be configured to allow independentadjustment of the base and length of the triangle. For an ellipticalshape, the adjustments could be major and minor elliptical dimensions.For cavities of other shapes, the appropriate dimensional adjustmentscan be implemented. The adjustments to fit the cavity dimensions can beused to determine overall therapeutic energy dose in Joules, or othersettings such as power, time, etc.

The sheath 130 can be attached to the handpiece 180 and functions toshield the electrodes 160 a-z while the handheld implement 101 is beinginserted into an aperture of a hollow body organ (when the device iscollapsed). The sheath 130 can shield at least the side electrodes (161,162) or all electrodes 160 a-z during insertion of the device throughthe organ aperture. The sheath 130 can be constructed to have anatraumatic tip. When collapsed, the head 110 can slide into the sheath130. Alternatively, the user can slide head 110 out of the sheath 130 asmuch as desired during a procedure. The sheath 130 can be attached tovia a rigid coupling to length adjustment 182 (e.g., knob orattachment), such that moving the length adjustment moves the sheath inthe same direction by the same amount as the movement of the lengthadjustment.

The tube 133 may be a part of aspiration device 103, and may carryfluids from the cavy to reservoir 113. In some embodiments, the tube 133is attached to a small pump that allows for mechanically pumping thefluid into the tube 133 and collecting the fluid in the reservoir 113.The tube 133 can be constructed of any material that is rigid enough toform a tube and allows for sterilization. In some embodiments, the tube133 is composed of plastic, rubber, or metal. The tube 133 can beinserted through the handheld implement 101 and sheath 130 to allowinsertion through the organ aperture during the procedure. In anembodiment, tube 133 and reservoir 113 form a complete seal such thatair cannot enter the reservoir 113 during the process of ablation.

The aspirator port 140 located on the handpiece 180 is connected to anaspirator device 103, via tube 113 (and aspiration device 103 mayinclude a vacuum source used to evacuate the uterus from any body fluidscreated from the procedure, for example).

Optionally, connector 150 may be located on the handpiece 180 andfunctions to connect the electrodes 160 a-z to the power supply 102,which supplies the RF Energy. The connector 150 may comprise at leastone wire per electrode 160 a-z. The wires can connect from theelectrodes 160 a-z, through the sheath 130 to the handpiece 180 and thenout the connector 150 to the power supply 102. The connector 150 can bea plug-in having 6 or more tines. However, connector 150 is notnecessary

The electrodes 160 a-z function to apply the RF power to the organand/or lining of the organ. Each electrode 160 a-z has its own lead(wire) that connects the electrode to the power supply 102. In generalablation apparatus 100 contains segmented electrodes 160 a-zinterspersed with insulators 120, 121, and 122. In some embodiments, thesegmented electrodes 160 a-z are configured on the head 110 in a shapethat mimics the shape of the hollow body organ. In differentembodiments, head 110 may have different shapes. The shape of the head110 can include a generally triangular shaped, circular shaped,oval-shaped, and/or trapezoidal shape. By generally, this means that theshape can be somewhat rounded, meaning that the corners are not pointed,but are rounded. An example of a trapezoidal shape includes, forexample, a square edge at the distal end from the handpiece 180 and atriangular edge at the proximal edge to the handpiece 180.

The electrodes 160 a-z can be any type of electrodes known in the art,including slotted D-tube electrodes 161, D-tube electrodes 162, coilelectrodes 163, braided metal tube electrodes, bead-chain electrodes,point electrodes, and metallic accordion electrodes (examples can beseen in the other embodiments herein).

In some embodiments, ablation apparatus 100 contains from about 3 toabout 50 electrodes, including 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33,34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, and 49electrodes 160 a-z. In the embodiments, shown in FIG. 1, there are sixelectrodes 160 a-z located on the distal end (e.g., the base) ofablation apparatus 100.

The electrodes 160 a-z can be configured along the perimeter of anopening formed by head 110 (e.g., the perimeter of a triangle for a headdesigned for ablating the uterus). In an alternative embodiment, theremay also be electrodes throughout the middle (e.g., on a line bisectingthe triangle and/or throughout ablation apparatus 100 on a fan-likearrangement) and/or on the base of ablation apparatus 100 (e.g., base ofthe triangle). However, by keeping the electrodes only on the perimeterof the opening (so as to be deployed on the perimeter of a body cavity),the diameter head 110 while folded and the diameter of sheath 130 can bekept smaller than when there are electrodes within the opening formed bythe head, so that inserting the sheath into the cavity creates lessdiscomfort to the patient and is less invasive. The electrodes 160 a-zfunction to deliver the RF energy to the tissue. By maximizing thecircumference and therefore the area of the electrodes, the charge onthe electrodes is spread out over a larger area, and therefore lessconcentrated. The larger surface therefore makes it less likely that theelectrodes will char the uterus or another hollow organ during ablation.In the case where the electrode dimensions are round and tubular, onlythe outermost semicircular surface of each round tubular electrode is incontact with the perimeter of the surface area of the hollow organ, withthe innermost semicircular area not contributing to effective contact.In the case of the round a tubular, it is possible to remove theinnermost semicircular region to form a tubular electrode with a “D”cross section. The “D” cross section allows for efficient packing ofright and left halves of the head 110 (e.g., electrodes 160 a-z) whenfolded up prior to deployment, reducing the overall dimensions of thehandheld implement 101 for either insertion through a natural orifice,or through an incision. This can be important when attempting tominimize handheld implement 101 cross-sectional area for minimal traumato the patient or to reduce anesthesia requirements to control pain. Thecross section of two circular electrodes within a tube of radius r canbe calculated as follows. Each electrode has a radius or r/2, and eachhas a circumferences of 2(r/2)π=rπ. The surface area of each theseelectrodes is Lrπ. If the same tube is filled with two D-shapedelectrode, each D shaped electrode can have a circumference of2rπ/2+2r=rπ+2r=r(n+2), and the surface area is Lr(π+2). The ratio of thelargest part of D-shaped electrodes to the largest pair of circularelectrodes that fits into the same tube is2Lr(π+2)/(2Lrπ)=1+2/π=1.6366˜1.64. Thus, the D-shaped semicircularelectrodes have about a 64% larger surface area than the circularelectrodes. However, if the corners of the D are rounded, although theD-shaped electrodes will still have a larger surface area, the D-shapedelectrodes will not have a 64% larger surface area. Since in particular,it is believed that the pain associated with requiring dilation of anelastic natural orifice, in particular the uterine cervix, is dependenton the diameter of the dilated orifice, the D-shaped electrodescross-sectional geometry allows for a greater contact area with thehollow body organ tissue without the additional pain associated with thefurther dilation required by a folded device cross sectional area of twocircular tubes. Thus, in some embodiments, the electrodes are D-tubeelectrodes (161, 162), which make it easier to configure the ablationapparatus 100 to close up into a compact structure and which reduces thedensity of the energy at the electrodes, thereby allowing the electrodesto deliver a large amount of energy to the uterus for ablation. Usingthe D-shaped electrode the cross sectional area of the sheath holdingthe head while the head is folded is minimized or at least reduced to besignificantly less than would be required for electrodes having acircular cross section to achieve a similar quality of ablation (e.g.,depth of ablation in the center other of the head without charring orotherwise over heating the perimeter). Other noncircular shapes thatreduce the necessary diameter of the sheath that holds the head could beused.

The handheld implement 101 can collapse upon itself using any methodsknown in the art. The embodiment in FIG. 1A, shows a method thatinvolves pulling the side of the electrode portion of the device of head110 into a sheath 130, which folds insulator 122 and causes electrodes162 to meet one another and electrodes 163 to meet one another andelectrodes 161 to meet each other. In some embodiments, the handheldimplement 101 may have push/pull-wires attached to the inside of thedistal portion of the slotted D-tube electrode 161 on the round side.Pushing on these wires would cause the D-tube electrodes 162 to bendoutward, causing the overall width of the handheld implement 101 toincrease. In some embodiments, an insulating layer is attached to theflat sides of the slotted D-tube electrodes 161 and/or D-tube electrodes162 and/or coil electrodes 163 to keep the D-tube electrodes fromshorting out when the handheld implement 101 is collapsed and/or fromshorting in the region near the opening of the sheath while deployed.

In some embodiments, there are two coil electrodes 163 along the distaledge of the handheld implement 101 (distal from the handpiece 180). Thetwo coil electrodes 163 allow for lateral expansion and retraction.Tubular electrodes along the side 160 a-z can alternate with springelectrodes 163.

To increase the penetration of the radio frequency energy withoutcausing charring of the tissue surface near the electrodes, it is alsopossible to cool the electrodes 160 a-z by various means, includingrunning flowing fluid through the ablation apparatus 100 or using gasexpansion, phase change, or other means. However, tubes for bringingcooling fluids to the cavity tend to increase the diameter required forthe sheath 130.

In the embodiments shown in FIG. 1A, there are two slotted D-tubeelectrodes 161 proximal to the sheath 130. The slotted D-tube electrodemay be a stainless steel D-tube that has cuts in the round side of the“D” which allows the electrode to flex along the flat side of the “D”.The slotted D-tube electrodes 161 can be oriented so the flat side ofthe “D” is pointing towards the middle of the handheld implement 101. Inthe embodiment shown in FIG. 1A, there are two D-tube electrodes 162 oneon each side. The D-tube electrodes 162 are stainless steel D-tubes. TheD-tube electrodes 162 can be oriented so the flat side of the “D” ispointing towards the middle of the handheld implement 101. The sideD-tube electrodes 162 can be hollow to allow insertion of the electrodes160 a-z and/or insulators 120, 121, and 122 on the base to adjust thewidth on the base.

In the embodiment shown in FIG. 1A, there are two coil electrodes 163.The coil electrodes 163 can reside inside the D-Tube electrodes 162 andcan be slid out via the width adjustment 184 on the handheld implement101. The coil electrodes 163 can be D-shaped.

The handpiece 180 functions to allow the user to position the handheldimplement 101 to change the shape of the handheld implement 101 and/orto collapse the head 110 (e.g., generally triangular electrode end) ofthe handheld implement 101. The power supply 102 and/or controller 104can be connected to the electrodes 160 a-z via a connector 150 on thehandpiece 180. While folding, electrodes 163 slide into an opening atone end of insulators 121, and while unfolding, electrodes 163 slide outof an opening at one end of insulator 121. While folded electrodes 161may be stored in the hollow space within insulators 120, insulators 121,and/or the conductors 162 between insulators 120 and 121. The hollowspace within conductors 162 may be insulated so that head 110 isfunctional while electrodes 163 are partially within the hollow spacewithin electrodes 162, and head 110 is not fully unfolded. Insulatingthe interior surface of the electrodes 162 allows electrodes 162 to notshort with electrodes 163 when not fully unfolded and allows head 110 toadjust to cavities of different sizes, and still be operational.

The handpiece 180 may include a connector 150, an aspirator port 140,the length adjustment 182 and a width adjustment 184 for deploying thedevice. The length adjustment 182 is located on the handpiece 180 andcan be knobs, sliders, etc. The length adjustment 182 functions tochange the effective length of the deployed device to accommodate avariety of different sized organs. The length adjustment 182 changes thelength of the sides of the generally triangular head of the head 110 andcan pull the sheath back, exposing more and more of the device. Thelength adjustment 182 allows for pushing the sheath 130 completely oralmost completely over head 110 to allow for insertion through a smallaperture, such as by the use of pull wires, push wires, and/or acombination thereof.

The width adjustment 184 is located on the handpiece 180 and can beknobs, sliders, etc. The width adjustment 184 functions to change themaximum width of the deployed device to accommodate a variety ofdifferent sized organs. The width adjustment changes the size of thebase of the generally triangular head of the device 110. In theembodiments shown in FIG. 1A, the width adjustment 184 can push out thecoil electrodes 163, allowing the device to open up wider (e.g., thebase to widen). The width adjustment and/or length adjustment can beattached to pull wires, push wires, and/or a combination of these thatare attached to the head 110 at the sides, front or bottom to effectmoving of the sides or base. The push and/or pull wires can be insertedthrough the side electrodes 160 a-z and/or insulators 120, 121, and 122.

Although in the embodiment of FIG. 1A length adjustment 182 and widthadjustment 184 are implemented by sliding two knobs within slots thatare parallel to one another, in another embodiment (e.g., which will bediscussed further below in conjunction with FIG. 7) the knobs may slideis slots that are perpendicular to one another.

Foot control 186 may be used for starting and/or stopping the ablation.By providing foot control 186, both of the user's hands are free formanipulating handheld implement 101 and/or controller system 104.

FIG. 1B shows controller system 104 and a page of the user interfaceassociated with controller 104. Controller system 104 of FIG. 1B mayinclude on-light 188 a, head image 188 b, power column 188 c, timecolumn 188 d, impedance column 188 e, screen 188 f, voltage port 188 g,aspiration port 188 h, instruction box 188 j, back button 188 l, andwarning light 188 m. In other embodiments, controller system 104 mayhave other features in addition to and/or instead of those listed inFIG. 1B.

On-light 188 a is a light that may turn on to indicate that controllersystem 104 is on and/or ablation is currently in progress. Head image188 b is an image of head 110, which indicates the current width andlength settings that of controller system 104, which may be used fordetermining an appropriate power output and duration of ablation formodes 1 and 2. Changing the width and length settings of the head maychange the power output and duration of ablation that is determined bycontroller system 104 to be appropriate. Power column 188 c is optionaland shows a column of numbers that indicate the power that will beapplied during modes 1 and 2 of ablation if the current settings areused (modes 1 and 2 will be described below in conjunction with FIG.1D). Time column 188 d is optional and shows a column showing theduration of time that the power of the corresponding row in the powercolumn may be applied during ablation. In an embodiment, there are tworows. One row (e.g., the top row) contains the power and time associatedwith mode 1, and the second row (e.g., the bottom row) contains thepower and time associated with mode 2. Impedance column 188 e isoptional, and shows the impedance measured for the region in which thecorresponding mode is being applied. In an embodiment, the impedance inthe top row is the impedance measured for the region in which mode 1 isbeing applied, and the impedance in the bottom row is the impedancemeasured for the region in which mode 2 is being applied. The impedancemeasurement could be used as an indication as to whether or notcontroller system 104 is functioning properly. For example, if theimpedance is significantly lower or higher than expected for the cavityof interest, it may be an indication that controller 104 is notfunctioning properly and/or that there is something unexpected presentor missing from the cavity of interest. Screen 188 f is the screen oncontroller 104 upon which output information is displayed. Voltage port188 g may be used for connecting handheld implement 101 to controllersystem 104. The voltage port 188 g may deliver the appropriate voltageto the electrodes of head 110 to deliver a desired power for a desiredperiod of time to cause an appropriate ablation of the walls of thecavity of interest. Aspirator port 188 h may be used for connecting atube via which fluids may be evacuated from the cavity of interest. Inan embodiment, controller 104 includes a pump that may be used forremoving fluids from the cavity of interest. In contrast to otherdevices, however, it is not necessary to create a vacuum in the cavityof interest to effectively ablate the cavity of interest. Instructionbox 188 j is optional, and may contain instructions to the user, such ashow to start ablation, a parameter was not yet inputted, how to inputsettings, and/or other messages. Back button 188 l may be used to returnto a prior screen to enter settings, such as the width and length of thehead while in the cavity of interest. Warning light 188 m may be used toindicate a problem, such as a short circuit or that a parameter has notyet been entered.

FIG. 1C shows a screen shot of another screen of a user interface of thecontroller system. FIG. 1C shows on-light 188 a, voltage port 188 g,aspirator port 188 h, instruction box 188 j, back button 188 l, andwarning light 188 m, which were discussed above in conjunction with FIG.1B. FIG. 1C also shows width setting 190B, length setting 190 c, screen190 d, decrement button 190 h, increment button 190 i, and next button190 g. In other embodiments, controller system 104 may have otherfeatures in addition to and/or instead of those listed in FIG. 1C.

Width setting 190 b may display the width input by the user. Lengthsetting 190 c may display the length input by the user. The width andlength setting may be entered via a keypad, increment, and/or decrementbuttons. Alternatively, the length and width settings may be entered viafields on the display of controller 104 and/or may be determinedautomatically based on by detecting the positions of the lengthadjustment 182 and width adjustment 184 (FIG. 1A). Screen 190 d may beused for viewing and/or entering the width and length settings ofcontroller 104. Decrement button 190 h may be used for decrementing thelength and or width setting of controller 104. Increment button 190 imay be used for incrementing the length and/or width setting ofcontroller 104. Controller 104 may have a touch screen, keypad, and/ortracking device via which one of the width setting 190 b or the lengthsetting may be selected. Upon activation (e.g., by touching the screenor entering input via a tracking device or keypad), decrement button 190h or increment button 190 i may be used to decrement or increment,respectively, the current setting that is selected (width or length).Next button 190 g may be used to go to the next page of the userinterface of controller system 104.

FIG. 1D provides an example in an embodiment in which ablation apparatushas 6 electrodes. In FIG. 1D, the six electrodes are numbered 1-6.Electrodes 161 may be an embodiment of one of electrodes 1 and 6,electrodes 162 may be an embodiment of one of electrodes 2 and 5, andelectrodes 163 may be an embodiment of one electrodes 3 and 4 (FIG. 1A).In mode 1, the top four electrodes are activated such that electrodes 3and 5 have a negative charge while electrodes 2 and 4 have a positivecharge, and electrodes 3 and 5 have a positive charge while electrodes 2and 4 have a negative charge. As the AC current applied to electrodes2-5 alternates, which pair of electrodes (the pair having electrodes 3and 5 or the pair having electrode 2 and 4) is positive and which pairis negative alternates. In mode 2, one of electrodes 1 and 6 ispositively charged and the other is negatively charged. An alternatingvoltage is applied to electrodes 1 and 6, such that which of electrodes1 and 6 is positively charged and which is negatively chargedalternates. In an embodiment, first mode 1 is applied to electrodes 2-5,using a particular voltage and duration of time of application, and thenmode 2 is applied using a different voltage and for a different durationof time. The region enclosed within electrodes 2-5 is larger then theregion between electrodes 1 and 6, and therefore (e.g., during mode 1)voltage is applied for a longer duration of time and/or the voltageapplied is higher, when compared to the voltage applied to electrodes 1and 6 (e.g., during mode 2). Applying more energy and power toelectrodes 2-5 than to electrodes 1 and 6 facilitates ablating thecavity without charring or otherwise over ablating the region betweenelectrodes 1 and 6.

In an embodiment, the power applied during modes 1 and 2 and theduration of time that the power is applied during modes 1 and 2 is givenin Table 1, below.

TABLE 1 Parameters for Power (watts) and Time (seconds) Mode 1 Power (W)W(cm) × L(cm) 4.0 4.5 5.0 5.5 6.0 6.5 2.0 58 59 61 63 64 66 2.5 58 59 6163 65 67 3.0 58 59 61 63 66 69 3.5 60 62 63 66 69 72 4.0 65 67 68 71 7477 4.5 70 71 73 75 78 82 Mode 2 Power (W) W(cm) × L(cm) 4.0 4.5 5.0 5.56.0 6.5 2.0 18 23 28 32 37 42 2.5 18 23 28 32 37 42 3.0 18 23 28 32 3742 3.5 20 24 28 33 37 42 4.0 23 27 30 34 38 42 4.5 26 29 32 35 39 42Mode 1 Time (sec) W(cm) × L(cm) 4.0 4.5 5.0 5.5 6.0 6.5 2.0 60 60 60 6060 60 2.5 72 72 72 72 72 72 3.0 84 84 84 84 84 84 3.5 96 96 96 96 96 964.0 108 108 108 108 108 108 4.5 120 120 120 120 120 120 Mode 2 Time(sec) W(cm) × L(cm) 4.0 4.5 5.0 5.5 6.0 6.5 2.0 30 30 30 30 30 30 2.5 3030 30 30 30 30 3.0 30 30 30 30 30 30 3.5 30 30 30 30 30 30 4.0 30 30 3030 30 30 4.5 30 30 30 30 30 30

In each of the four tables of table 1, the choice of the row is based onthe width of the cavity, while the choice of the column is based on thelength of the column. The units of widths and lengths are given incentimeters, time is in seconds, and the units of power are in Watts.So, for example, for a uterus that is 3 cm wide and 5.5 cm long, duringmode 1, 63 Watts may be applied for 84 seconds, and during mode 2, 32Watts may be applied for 30 seconds. Table 1 was determinedexperimentally by placing head 110 a small triangular cavityapproximating the uterus between two pieces of meat, then treating meatwith head 110, and finally measuring the depth of treating of the meat.The power applied may be determined by iteratively applying a voltage,measuring the current and determining the power for the product of P=IV(power=current times voltage). Depending on whether the power is toohigh or too low, the voltage is raised or lowered and then the currentis measured again and the power is computed again to determine whetherthe output power is within a desired range. The process of adjusting thevoltage, measuring the current and computing the power is repeated untilthe output power is correct (it may take only a few seconds).Optionally, once the current is measured during the initial iteration,the impedance may be calculated, and the calculated impedance may beused to predict the voltage that will give the desired power output. Theoptimum values for ablation in humans may be somewhat different than forthe meat, but should be similar. In alternative embodiments, electrodes1 and 6 may be replaced with multiple pairs of electrodes and electrodes2-5 may be replaced with multiple pairs of electrodes. In alternativeembodiments, the cavity may be divided into more than two regions, andthere may be more than two modes applied.

FIG. 2 shows a block diagram of a controller system 200 used in methodsof ablating hollow body organs. The controller may include output system202, input system 204, memory system 206, processor system 208,communications system 212, vacuum/pressure device 214, algorithm 213,lookup table 216, voltage converter 218, electrode 222 a-z, lead 228,signal generator 220, relay 224, relay 226, and ammeter 230. In otherembodiments, the controller system used in methods of ablating hollowbody organs 200 may include additional components and/or may not includeall of the components listed above.

The controller system 200 is an example of a controller that may be usedin the ablation apparatus 100 in combination with the power supply 102to control the radio frequency (RF) amount and treatment length (seeFIG. 1A). Controller system 200 may be an embodiment of controller 104(FIG. 1A). In some embodiments, the controller controls the frequency ofalternating current (AC) from the RF generator to each electrode 160 a-z(FIG. 1A) in ablation apparatus 100. Alternatively, the controller 200can control each set of electrodes 160 a-z separately (e.g., the sideelectrodes and the distal electrodes). With reference to FIG. 1A, theelectrodes 160 a-z can be separately controlled through separate wiresattached from the electrodes 160 a-z to the power supply 102 andcontroller 104. In some embodiments, the controller includes analgorithm that allows for the control of the AC to each electrodes 160a-z. In some embodiments, the controller 200 makes it possible toutilize electrode polarities of various combinations to effect bipolarablation between selected electrodes. In some embodiments, thecontroller 200 makes it possible to utilize electrode polarities ofvarious combinations to effect monopolar ablation to a neutralelectrode. The RF power source (FIG. 1A, 102) and controller 200 arecapable of driving multiple electrodes in various bipolar pairs locatedalong the handheld implement 101 and in proximity to the perimeter ofthe hollow organ, so as to automatically sequence through the desiredset of bipolar or monopolar ablation polarities (e.g., an algorithm).

In some embodiments, the algorithm designed by the controller is an RFpower of between about 30 watts and 90 watts, including but not limitedto, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47,48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65,66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83,84, 85, 86, 87, 88, and 89 watts. In some embodiments, the power isapplied for a time of between about 10 seconds to about 200 seconds,including but not limited to, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20,21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38,39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56,57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74,75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92,93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108,109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122,123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136,137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150,151, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164,165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177, 178,179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 191, 192,193, 194, 195, 196, 197, 198, and 199 seconds. In some embodiments, themethod includes more than one mode and/or algorithm. For example, thetwo modes may be different modes applied to different electrodes atdifferent times. Examples of these modes are discussed above inconjunction with FIG. 1D. In some embodiments, the user can change theamount of time or power during the procedure based on how the modeand/or algorithm is working on the organ they are currently treatingand/or based on the dimensions and/or other characteristics of thecavity being ablated. In some embodiments, the power and time parametersare used as shown in Table 1. The width and length are measured andbased on the measurements the appropriate parameters used in each mode.In some embodiments, a frequency of between about 360 and 560 KHz isused, including but not limited to 370, 380, 390, 400, 410, 420, 430,440, 450, 460, 470, 480, 490, 500, 510, 520, 530, 540, and 550 KHz. Forexample, in an embodiment, the frequency that is used is 460 Hz. In someembodiments, the current is between about 1.4 and 2.4 amps, includingbut not limited to, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, and 2.3amps. In some embodiments, the current is between 1.5 and 2 amps.

In some embodiments, the voltage is adjusted and the current measureduntil the power (P=IV) is at the desired value. The current needs to bemeasured, because the resistance will vary depending on the individual,but for the uterus is of an order of magnitude of about 20 ohms. Thewidth of the uterus is typically between about 2 and 4.5 cm while thelength is between about 4 and about 6.5 cm. The endometrium is betweenabout 5 and about 10 mm thick. Under the endometrium is the myometrium.In some embodiments, the ablation does not heat the myometrium.

Output system 202 may include any one of, some of, any combination of,or all of a monitor system, a handheld display system, a printer system,a speaker system, a connection or interface system to a sound system, aninterface system to peripheral devices and/or a connection and/orinterface system to a controller system, intranet, and/or interne, forexample.

Input system 204 may include a key pad and/or touch screen for enteringthe dimensions of the cavity of interest (e.g., the uterus). Examples ofthe keypad and touch screen are discussed further in conjunction withFIGS. 1B and 1C. Alternatively, any one of, some of, any combination of,or all of a keyboard system, a mouse system, a track ball system, atrack pad system, buttons on a handheld system, a scanner system, amicrophone system (e.g., for a voice activated system), a connection toa sound system, and/or a connection and/or interface system to acontroller system, connection to a an external storage device such as anEEPROM, SD, MMC, mini-disk or other storage media or medium located inthe handpiece, intranet, and/or internet (e.g., IrDA, USB), for example.Input system 204 allows the user to interact with the controller and RFgenerator to choose an algorithm, power, and/or time for ablation (e.g.,by entering the parameters of the cavity). Alternatively, the user maychange or vary an algorithm, power and/or time.

Memory system 206 may include, for example, any one of, some of, anycombination of, or all of a long term storage system, such as a harddrive; a short term storage system, such as random access memory; aremovable storage system, such as a floppy drive or a removable drive;and/or flash memory. Memory system 206 may include one or moremachine-readable mediums that may store a variety of different types ofinformation. The term machine-readable medium is used to refer to anymedium capable carrying information that is readable by a machine. Oneexample of a machine-readable medium is a controller-readable medium.Memory system 206 may contain one or more saved algorithms that drivemultiple electrodes in various bipolar pairs located along handheldimplement 101 and in proximity to the perimeter of the hollow organ, soas to automatically sequence through a desired set of voltages appliedto different electrodes of ablation apparatus 100. Memory 206 may storelookup tables, such as Table 1, for the determining the pattern,magnitude, and duration of time of the power applied to the cavity (byapplying a voltage to electrodes of ablation apparatus 100). Examples ofthe algorithm and lookup table are discussed above in conjunction withFIG. 1D.

Processor system 208 may include any one of, some of, any combinationof, or all of multiple parallel processors, a single processor, a systemof processors having one or more central processors and/or one or morespecialized processors dedicated to specific tasks. Processor system 208may implement the algorithms based on the lookup table of Table 1 thatare stored in memory 206 and input received from input system 204.

Communications system 212 communicatively links output system 202, inputsystem 204, memory system 206, processor system 208, vacuum/pressuredevice 214, and/or signal generator 220 to each other. Communicationssystem 212 may include any one of, some of, any combination of, or allof electrical cables, fiber optic cables, and/or means of sendingsignals through air or water (e.g. wireless communications), or thelike. Some examples of means of sending signals through air and/or waterinclude systems for transmitting electromagnetic waves such as infraredand/or radio waves and/or systems for sending sound waves.

Vacuum/pressure device 214 may be included within, attached to, or be anaspirator device (such as aspirator device 103, FIG. 1A).Vacuum/pressure device 214 may include a pump and may be controlled byprocessor system 208 and/or the keypad of input system 204 may linkdirectly to vacuum/pressure device 214 for turning vacuum/pressuredevice 214 on and off.

Lookup Table 216 may include values for the settings of the amount ofpower and time to be used for a hollow body organ of a certain size,stored in memory system 206. Optionally lookup table 216 may includeinformation about the pattern and/or modes in which the voltages areapplied. Lookup Table 216 can allow for looking up the size of a hollowbody organ by width and length. Table 1 may be an embodiment of lookuptable 216. Alternatively, the Lookup Table, or parts thereof may belocated in the Handpiece information storage means. In an embodiment,the catheter may include a chip that could configure the generator powerdelivery scheme by configuring controller 104 or by controller 104reading the power settings from the chip on the catheter. Having thelookup table on the catheter or on handheld implement 101 allows moreflexible energy delivery schemes since it's generally easier to update adisposable portion of hand unit 101 rather than updating controller 104.For example an EEPROM may store lookup table 216, and the EEPROM may beplaced in the connector or the housing of handheld implement 101. TheEEPROM only requires 3 wires, and three pins of the connector may beused for the EEPROM.

Voltage converter 218 can convert the voltage from the electrical outletinto the voltage needed for ablation of a hollow body organ of a certainsize. Voltage converter 218 may include a transformer and/or powersupply.

Signal generator 220 may produce a signal of a particular frequency thatworks with the algorithm needed for ablation of a hollow body organ. Forexample, signal generator 220 may decide on the frequency and themagnitude of the voltage based on input from processor system 208, thatis sent to each electrode for an amount of time (the modes are discussedin conjunction with FIG. 1D, and the electrodes are discussed below inconjunction with electrodes 222 a-z).

The electrodes 222 a-z can function to transfer the signal to the partof the hollow body organ electrodes 222 a-z are in proximity to.Electrodes 1-6 of FIG. 1D, 161, 162, 163, and/or 160 a-z, may beembodiments of Electrodes 222 a-z. In some embodiments, the electrodescan function in pairs, triplets, quadruplets, quintuplets, or may allfunction together. In some embodiments, electrodes most distal tohandpiece 180 function for a different time and for a different powerthan the electrodes proximal to handpiece 180 (FIG. 1A).

Relays 224 and 226 may function to relay the signal from the signalgenerator to one or more groups of electrodes that are included withinelectrodes 222 a-z. A relay (e.g., 224 and/or 226) is an electricallyoperated switch. In an embodiment, relays 224 and/or 226 use anelectromagnet to operate a switching mechanism mechanically, but otheroperating principles are also used. Relays 224 and 226 allow the signalsfrom signal generator 220 to switch which group of electrodes signalsare sent. For example, one relay (e.g., 224) may function to sendsignals to the two electrodes proximal to the handpiece, such aselectrodes 1 and 6 during mode 2. The other relay (e.g., 226) mayfunction to send signals to the four electrodes distal from thehandpiece, such as electrodes 2-5, during mode 1. Relays 224 and 226 maybe replaced with other types of electrical and/or electromechanicalswitches, such as transistors, threshold diodes, and/or other thresholddevices. FIG. 2 provides an example of how the relays can function tosend signals separately to different groups of electrodes.

Alternatives and Extensions

FIGS. 3-5 provide alternative embodiments of the hollow body handheldimplement 101 of FIG. 1. In these embodiments, the design, organization,and number of the electrodes can vary. The design and movement ofablation apparatus 100 can also vary. Features of different embodimentscan be interchanged with features of other embodiments.

Ammeter 230 measures the current, which is read by processor system 208.Processor system 208 computes the power output based on the voltagesetting and the reading from ammeter 230, and adjusts the voltage untilthe power output is at the desired level as determined by lookup table216.

FIGS. 3A-C show overhead views of three embodiments of ablationapparatus 100 used in hollow body ablation apparatuses for methods ofablation of hollow body organs. The figures show embodiments of theablation apparatus 100 show the head without showing the handpieceassociated with the head. In some embodiments, the handpiece could beconstructed similarly to how handpiece 180 was described in FIG. 1A.

FIG. 3A shows a head 300A having three separate electrodes 304, thecenter electrode 304 including a sliding insulation sheath 306. Theelectrodes 304 also include atraumatic tips 302. Although not shown, thehead 300A can also include a handpiece 309. In other embodiments thehead 300A may not have all of the elements or features listed and/or mayhave other elements or features instead of or in addition to thoselisted.

In FIG. 3A, there are three electrodes 304 that can open up in thecavity of the hollow body organ. The three electrodes 304 can open upsimilar to a fan. Push or pull wires can be used to pull the outerelectrodes toward the central electrode 304. The center electrode 304includes a sliding insulation sheath 306 which can be pushed up when thehead 300A is being collapsed. Alternatively, each of the outer twoelectrodes 304 can be a D-tube electrode having an insulated layer onthe straight edge of the D-tube. The straight edge of the D-tube can beplaced closest to the middle one of electrodes 304 on each outerelectrode 304. In some embodiments, the sheath 306 can be moved up ordown on the central electrode 304 using one or more control knobs on thehandpiece 309.

The atraumatic tips 302 on the distal ends of the electrodes from thehandpiece function to keep the electrodes 304 from touching the sides ofthe hollow body cavity aperture. Each electrode 304 can have anatraumatic tip 302 on the end of the electrode 304. In some embodiments,the center electrode 304 can be completely covered by the sheath 306making it unnecessary for it to have an atraumatic tip 302.

The sheath 306 can act as a sliding insulator to keep the outerelectrodes 304 from touching the inner electrode 304. The sheath 306 canbe a layer of insulation on the central electrode 304 that can slidedown the electrode 304, controlling the flow of energy in the hollowbody cavity.

Before treatment, the sheath 306 can be positioned to completely ormostly cover the central electrode 304. Positioning sheath 306 to covercentral electrode 306 causes the energy to transfer only at the distalportion of handheld implement 101. After that section of the hollow bodyorgan is fully treated, the sheath 306 can be pulled back, exposing moreof the electrode 304 and allowing the newly exposed electrode 304 totreat the tissue. Alternatively, the sheath 306 can be positioned tocover the center electrode 304 while handheld implement 101 is collapsedand inserted through the aperture of the hollow body organ and then thehead 300A can be opened (e.g., the electrodes 304 separated) and thesheath 306 removed before the RF energy is applied.

FIG. 3B shows an embodiment of an ablation device 300B that uses slidingbead-chain electrodes 312. Using sliding bead-chain electrodes 312 is analternate approach, for example, for an endometrial ablation device. Theablation device 300B includes side electrodes 336 (shown cut-away),insulator 314, insulator 316, bead-chain electrodes 312, a centralpush/pull-wire 330, and two side push-pull wires 332. The ablationdevice 300B can also include a handpiece 309. In other embodiments,ablation apparatus 300B may not have all of the elements or featureslisted and/or may have other elements or features instead of or inaddition to those listed.

The side electrodes 336 can be tubular and hollow in structure and canfunction to house the bead-chain electrodes 312. The bead-chainelectrodes 312 can be a series of metallic beads separated by a thinwire, making the structure very flexible but with a fairly high surfacearea. The structure of the bead-chain electrodes 312 is similar to whatis found on some necklaces and key chains.

The insulators 316 can reside inside the side electrodes 336 andfunction to insulate the side electrodes 336 from the bead-chainelectrodes 312. The insulators 316 can also be attached at the distalend of the device between the two bead-chain electrodes 312.

The push/pull-wires 334 and 328 can be connected to the bead-chainelectrodes 312 and allow the user to extend or retract the bead-chainelectrodes 312 as needed. The push/pull-wires 334 can pull the sidestogether to collapse the top two electrodes 312 upon each other creatingtwo straight parallel lines of electrodes 312. A central push/pull wire332 can be implemented to widen the device 300B. In an embodiment, twosided push/pull wires 332 are made from a flexible resilient materialthat acts as a spring pushing the head open.

FIG. 3C shows an embodiment of an ablation head 300C that uses metallicaccordion electrodes 320. Ablation head 300C is an alternate approachfor an ablation device (e.g., an endometrial ablation device). Ablationhead 300C can operate very similarly to the sliding bead-chain concept(see FIG. 3B) with the major exception being that, instead of abead-chain for an electrode, this concept uses a metallic accordion-likestructure as the electrode. The accordion structure 320 can be flexibleand conductive and can bend as well as change length. Push/pull wires326 can be used to push the accordion-like electrodes 360 together atthe base and/or to push them apart.

FIG. 4 shows an overhead view of an embodiment of an ablation device 400used in a hollow body ablation apparatus for methods of ablation ofhollow body organs. The ablation device 400 uses a central slidinginsulator 421 to insulate electrodes 462. The ablation device 400 canuse extension spring electrodes 461 for width adjustment and push-wires436 to extend the head 410 from a central push/pull wire 438 attached toa hypotube 436. The extension spring electrodes 461 and the push wires436 allow for collapsing the head 410 of the device 400 and to changethe shape or size of the head 410 of the device.

The ablation device 400 may include a handpiece (not shown), electrodes460 a-z, extension spring electrodes 461, braided metallic electrodes462, insulators 420, fixed insulators 421, central push wires 436, twoouter push wires 436, braided tube rings 437, tip connections 480,electrical connections 470, and push-pull wires 438, distal insulatinggaps 422, sliding insulators 420, and fixed insulators 421. In otherembodiments the hollow body ablation apparatus 400 may not have all ofthe elements or features listed and/or may have other elements orfeatures instead of or in addition to those listed.

The purpose of the sliding insulator 420 is to direct the flow of energyin the hollow body organ. When the sliding insulator 420 exposes onlythe distal portion of the braided metal tube electrode 462, energy isonly delivered to the distal portion of the organ. When the slidinginsulator 420 is pulled back, energy is delivered the newly exposedregions until the full uterus is treated.

In FIG. 4, the braided metal tube electrodes 462 are similar to (or maybe) coaxial cables and are positioned on the device 400 as sideelectrodes. Each braided metal tube electrode 462 can have anon-conductive core, in between the outside wires and the inside wires,that would allow braided metal tube electrode 462 to be flexible. Thebraided metal tube electrodes 462 can be flexible. The braided metaltube electrodes 462 may also contain a ring 437 to keep the braidedtubing from unraveling. The braided metal tube electrodes 462 can beattached to the extension springs 461 via connections 480. Theconnections 480 can be insulators 420 or can be atraumatic materials.

The distal electrodes 461 are extension spring electrodes that may belocated at the distal end of the head (on the base of the device 400).The distal electrodes 461 function to treat the distal region of thehollow body organ (e.g., the fundus region of the uterus). The distalelectrodes 461 can stretch to accommodate a variety of widths (e.g.,uteri widths). The distal electrodes 461 can include a connection 480that functions to connect the distal electrodes 461 to the centerconductive core of the braided metal tube electrodes 462 (e.g., coaxialcable).

The distal insulating gap 422 functions to insulate the extension springelectrodes 461 from each other. The distal insulating gap 422 becomesthe tip of the device 400 upon collapsing. The distal insulating gap 422can be silicone.

The push wires 436 allow for width adjustment by connecting to thedistal corners of the device 400. The push wires 436 push on distalcorners and widen the distal end of the device (the base). The pushwires 436 can extend the extension springs to increase width of thedistal end of the head 410. Activation of push wires 436 can be at theproximal end of the device (e.g., the handpiece 180).

The sliding insulator 420 functions to collapse the device 400 and/or towiden the device. The sliding insulator 420 slides on top of the braidedmetal tube electrodes 462 and directs the flow of energy in the hollowbody organ (e.g., uterus). The sliding insulator 420 can be moved byconnecting a push wire 438 to it which can be actuated at the proximalend of the device 400 (at the handpiece 180).

The handpiece 180 can be constructed similarly to any embodimentdescribed herein, for example see FIG. 7 and/or FIG. 1A. The handpiece180 can contain knobs to allow for sliding of the sliding insulator 420to cover the braided metallic electrodes 462 and/or to collapse thedevice 400 for insertion into an aperture of a hollow body organ. Thehandpiece may also contain electrical connections 170 that connect theelectrodes 462, 461 to the RF power source.

FIG. 5 shows an overhead view of an embodiment of an ablation device 500used in a hollow body ablation apparatus for methods of ablation ofhollow body organs. The ablation device 500 uses telescoping electrodes563 to change the length and/or width and/or to collapse the device 500.

The ablation device 500 may include telescoping electrodes 563 a-z, asheath 530, joints or electrically insulating couplings 580, a head 510,and a tubular electrode 564. In other embodiments the hollow bodyablation apparatus 500 may not have all of the elements or featureslisted and/or may have other elements or features instead of or inaddition to those listed.

The telescoping electrodes 563 may include two pieces 561 and 562. Piece1 562 and Piece 2 561 can fit together as two sleeves, one sliding intothe other sleeve. The dotted line on Piece 2 in FIG. 5 shows a wire fordelivering electricity to the electrodes. Using piece 2 561, the lengthof the telescoping electrode 563 can be changed by moving Piece 1 562 upor down.

Piece 1 562 can be a straight line with an inner polymer tube and twoouter hypo tubes glued to the inner polymer tube. The inner polymer tubecan be between about 4.0 to 4.6 cm long, including but not limited to4.1, 4.2, 4.3, 4.4, and 4.5 cm long. In other embodiments, the innerpolymer tube is about 4.3 cm long. The two outer hypo tubes can be of alength equal to the length of the inner polymer tube minus a smallnotch. The length of the notch can be about 1 mm to 3 mm, including 1.1,1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5,2.6, 2.7, 2.8, and 2.9 mm. The small notch can be filled with glue. Thelength of the outer tubes can be from about 1 to about 2 cm and fromabout 2 to about 3 cm long with glue filling the middle notch. In someembodiments, the inner tube is approximately 4.3 cm, and the outer hypotubes are 1.5 cm and 2.5 cm with glue filling the middle notch.

Piece 2 561 can be a longer piece that is generally with one inner tube,an outer tube that covers and is parallel to the inner tube. Piece 2 561can include a central tube washer or disk with a narrow polymer tubeglued in. The outer tube can be a larger diameter SS hypotubes, sized tofit over and “telescope” the smaller SS hypotubes (Piece 1) 562. Whenpiece 2 561 is inserted over Piece 1 562, it can form a two-sectionadjustable length electrode (a telescoping electrode) 563.

The electrodes 563 a-z can be configured on the head 510 such that thetelescoping electrodes 563 a-z are separated from each other by anelectrically insulating coupling 520. Two telescoping electrodes 563 arepositioned on the base (distal side) of the head 510 separated by acouplings 520 a-z. One or two telescoping electrodes can also be placedon either side of the head 510. Alternatively, one telescoping electrode563 can be placed on each side and one proximal electrode 564 can beplaced separated by an electrically insulated coupling 520. The proximalelectrode 564 can be 1.5 cm long. The telescoping electrode 563 can varyfrom about 2.5 cm to about 5 cm (depending on whether Piece 1 562 andPiece 2 561 are pulled apart or pushed together). In some embodiments,the telescoping electrodes on the base can vary from about 2 cm to about4 cm, depending on whether Piece 1 562 and Piece 2 561 are pulled apartor pushed together.

Two of the adjustable telescoping electrodes 563 can form the sides of atriangular shaped electrode structure 510 (the head). The distal end ofthe triangle (which is the base of the triangle) can be similarlytelescoped to have adjustable width. The sides can also include atubular electrode 564 separated from the telescoping electrode 563 by anelectrically insulted coupling 520. The device 500 can also include asheath 530 that can be moved up and over the head 510 to collapse thehead 510 for insertion into an aperture of a hollow body organ.

Further embodiments of ablation devices can include a collapsible flexcircuit with a NiTi strip for support (a stronger wire). The NiTi shapememory alloy strip creates a loop shape to fit a uterus or other hollowbody organ. NiTi strips are superelastic fine-grained Nickel-Titanium(NiTi) polycrystalline shape memory alloys.

Further embodiments of ablation devices include, for example, aself-expanding spring device with a 2-4.5 cm width when completely openand 4-6.5 cm length when completely open. The springs can be theelectrodes or alternatively, the electrodes can be included as “islands”in the springs (e.g., electrodes can be woven into mesh as islands).Another alternative embodiment of an ablation device includes ametalized foam that acts like an accordion fan.

An Embodiment of the Handheld Implement

FIG. 6A shows an overhead view of an embodiment of the inside of ahandpiece 600 used in an embodiment of a hollow body ablation apparatusfor methods of ablation of hollow body organs. The handpiece 600includes a shell 602, a central tube 605, levers 610, 615, and 619,sliding member 613, width slot 612, aspirator tube 620, chamber 624,sliding piece 625, wires 626, wires 628, length slot 629, joints 632a-e, arrows 634 a-g, a vacuum port 640, a sheath 655, and wire post 665.In other embodiments the handpiece 600 may not have all of the elementsor features listed and/or may have other elements or features instead ofor in addition to those listed.

In short, the length and width adjustments on the handpiece 600 usepush/pull wires attached to levers, sliding members and/or the sheaththat function to change the length and width of the ablation deviceand/or to insert it into the sheath. The push/pull wires are attached tothe head of the device and are attached to levers and/or slidingmembers. Knobs on the handpiece are used to move the levers to effectchanges in position and/or to collapse the head into the sheath.

Handpiece 600 is another embodiment that may be substituted forhandpiece 180. The outer shell 602 of the handpiece can be in any shapeknown to the skilled artisan. In some embodiments it is in a shape thatmakes it more comfortable to the user to hold. In some embodiments, itis small enough that the user can hold it with one hand. The outer shell602 can be made of a material that is sterilizable without changing itsshape and/or properties.

The central tube 605 may be slidably attached to a chamber to which thesheath is connected. The central tube 605 may be attached within thesheath (not shown) to push/pull wires for movement of electrodes 3 and 4(see FIG. 1D) in and out of the insulating tubes separating electrodes 3and 4 from electrodes 2 and 5. Central tube 605 may be connected to asliding piece mounted in channels outside of the walls of the chamber.Central tube 605 may slide inward and outward within a hole in one ofthe walls of the chamber as the sliding piece slides. Central tube 605may be referred to as a push/pull tube, and central tube 605 isconnected to push/pull wires. Pushing and pulling central tube 605pushes and pulls, respectively, the push/pull wires pushing conductors 3and 4 out or pulling conductors 3 and 4 in.

Lever 610, width slot 612, sliding member 613, lever 615, and lever 619are used for changing the width of the head. The width adjustment can beeffected by sliding one of the knobs on the outside of the handpiece 600right or left on the handpiece within a slot 612. The knob is attachedto the sliding member 613, which moves levers 610 and 619. The leversare attached to a push/pull wire. The push pull wire has a fork or splitwhere the push pull wire divides into two push pull wires that areattached to the head/electrodes (3 and 4, FIG. 1D). As the push pullwires are pushed, electrodes 3 and 4 slide out of the insulatingD-shaped tubes between conductors 2 and 3 and between conductors 4 and 5(FIG. 1D). As the D-shaped coil electrodes 3 and 4 extend out of theinsulator tubes, electrodes 3 and 4 push against one another (via theinsulator separating electrodes 3 and 4), causing the head to widen intoa triangular shape. Moving the knob in the opposite direction reversesthe process bring electrodes 3 and 4 into the insulating tubes attachedto electrodes 2 and 5, respectively. Movement of the knob pulls thedistal electrodes (e.g., coil electrodes in FIG. 1A) into insulatorsand/or the sheath. The movement of the width adjustment can be at aright angle to the movement of the length adjustment so that it will bemore clear to the user which knob to use for the width adjustment, whichmay decrease confusion about which knob causes which adjustment.However, in some embodiments, the width adjustment and length adjustmentcan move in the same direction (see, for example, the embodiment in FIG.1A).

The length adjustment includes a length slot 629 a sliding member, and asheath (not shown). The length adjustment can be effected by sliding aknob up or down a slot 629 on the handpiece 600. The knob may be coupledto the sheath with a rigid coupling, such that moving the knob slidesthe sheath the same distance and in the same direction as the knob. Theslot 629 can be positioned on the handpiece parallel to the sheath and,thus, using the slot on the handheld implement 101, the movement of theknob can mimic the movement of the sheath up or down the handpiece.Thus, the knob is moved upward (distally) to lengthen and down(proximally) to shorten. Further, as the sheath moves up, the head canbe collapsed to have the two sides of the base parallel to each other sothat the majority of the head fits into the sheath. In this case, theknob is moved to the furthest distal position to collapse the head.Smaller movement of the knob results in smaller changes to the length ofthe head that is unsheathed.

Chamber 624 may be hermetically sealed. Central tube 605 may slide in aninward and outward direction within a hole in one of the walls ofchamber 624, thereby changing the width of head 110, if head 110 is atleast partially exposed or unsheathed. The sheath may be slidablyattached to chamber 624 and may slide in and out of chamber 624 toexpose or cover, respectively, portions of head 110, thereby changingthe length of head 110 that is exposed.

Sliding piece 625 may be slidably mounted in channels along side chamber624. Central tube 605 may be fixedly mounted to sliding piece 625, sothat when sliding piece 625 slides, central tube 605 slides with slidingpiece 625 in the same direction inward or outward with respect to a holein a wall of chamber 624.

Wires 626 may attach to electrodes 3 and 4, and wires 628 may attach toelectrodes 1, 2, 5, and 6 (see FIG. 1D and FIG. 2). Wires 626 may slidewith central tube 605 as the width of head 110 is adjusted.

The wires 626 and 628 function to transmit electricity to theelectrodes, which may have a frequency in the radio frequency range, forexample. As such, the wires 626 and 628 are attached to the electrodesin the head of ablation apparatus 100, and wires 626 are insertedthrough the central tube 605 while wires 628 enter chamber 624 on theouter side central tube 605 to attach to electrodes 3 and 4 andelectrodes 1, 2, 5 and 6, respectively. Wires 626 and 628 may also beattached through a connector to controller 104. In an embodiment, oneset of electrodes (e.g., 1, 3, and 5 of FIG. 1D) is connected to the onepolarity of the power source and another set of electrodes (e.g., 2, 4,and 6 of FIG. 1D) is connected to the other polarity of the powersource, such that as the polarity of the power source alternates, thepolarity of the electrodes alternate. In an alternative embodiment,there is one wire per electrode allowing for separate control of eachelectrode.

Slot 629 may hold the length adjustment knob, and the length adjustmentknob may be rigidly connected to the sheath (e.g., via a plasticconnector piece). As the length adjustment knob slides up and down slot629, the sheath may slide up and down covering or exposing, respectivelyportions of head 110, thereby adjusting the length of the head 110 thatis used for ablation according to the dimensions of the cavity. In someembodiments, as the sheath is moved up and over the head of the device,the width adjustment operates to push the sides together and to push thetwo sides of the distal end together to create a tubular head that canfit into the sheath (e.g., sheath 130 or 530).

Joints 632 a-e allow levers 610, 615, and 619 and sliding member 613 tomove. In an embodiment, joints 632 a-e may be pivots, which may be heldin place by screws. Joint 632 a attaches lever 615 to shell 602 so thatlever 615 rotates about joint 632 a. Joint 632 b attaches lever 615 tolever 619 so that lever 619 may rotate about joint 632 b as lever 610moves (the movement of lever 615 causes lever 619 to move). Joint 632 cattaches lever 610 to lever 615 so that lever 610 and 615 rotate withrespect to joint 632 c as lever 610 moves (which causes lever 615 tomove). Joint 632 d connects lever 610 and sliding member 613 so that assliding member 613 slides, lever 610 rotates about joint 632 d. Joint632 e connects lever 619 to sliding piece 625, so that as lever 619moves (and rotates with respect to joint 632 e), sliding piece 625slides pushing central tub 605. Joint 632 e is not connected to slidingmember 613.

Arrows 634 a-g are direction arrows showing the direction of movement oflevers 610, 615, and 619, sliding piece 625, and central tube 605 assliding member 613 slides in the direction of arrow 634 a. Specifically,as sliding member 613 slides in the direction of arrow 634 a, one end oflever 610 is pulled, via joint 632, in the direction of arrow 634 b(which is the same direction as arrow 634 a). As a result, the other endof lever 610 is pulled in the direction of arrow 634 c. The movement oflever 610, via joint 632 c, pulls on one end of lever 615, which causeslever 615 to rotate about joint 632 a (which is at the other end oflever 615) in the direction of arrow 634 d. The rotation of lever 615causes lever 615 to push, via joint 632 b, on one end of lever 619 inthe direct of arrow 634 e. The pushing on lever 615 causes the other endof lever 615 to push, via joint 632 e, on sliding piece 625. As a resultof the pushing on sliding piece 625, sliding piece 625 moves in thedirection of arrow 634 f, which causes central tube 605 to move in thedirection of arrow 634 g (which is the same direction as arrow 634 f).Moving sliding member 613 (via moving the width adjustment knob) in theopposite direction of arrow 634 a causes movement of levers 610, 615,and 619, sliding piece 625, and central tube 605 to move in the oppositedirection as arrows 634 b-g, in a similar manner as described above(except pushes are replaced with pulls and pulls are replaced withpushes).

The vacuum port 640 allows for the attachment of a vacuum tube to removefluid (i.e. liquids, vapors and gases) from the hollow body organ beforeduring and after the procedure. The tube can be placed from the vacuumport 640 through the handpiece to effect fluid removal in the hollowbody organ.

The sheath 655 functions to connect the wires 626 and 628 to thecontroller system. In some embodiments, the wires 626 and 628 arebundled into an electrical wire to produce the sheath 655. The sheath655 may allow for reversible attachment to the controller system toallow for separation of the device from the controller (e.g., via anelectrical plug-in).

The wire post 665 functions to immovably attach the wires 626 and 628from the sheath 655 to insertion through the housing 607.

FIG. 6B shows a cross sectional view of an embodiment of the inside ofhandpiece 600. The handpiece 600 includes a shell 602, a central tube605, levers 610, 615, and 619, sliding member 613, an aspirator tube620, chamber 624, sliding piece 625, wires 626, wires 628, a vacuum port640, and a sheath 655, and lead-wire post 665, which were discussedabove in conjunction of FIG. 6A. Handpiece 600 may also include widthknob 662, length knob 664, rigid coupling 666, and sheath 668. In otherembodiments the handpiece 600 may not have all of the elements orfeatures listed and/or may have other elements or features instead of orin addition to those listed.

Width knob 662 is rigidly fixed to sliding member 613. Thus when theuser slides width knob 662, sliding member 613 slides in the samedirection, and levers 610, 615, and 619, sliding member 613 translatethe sliding motion of width knob 662 into the sliding motion of centraltube 605. Length knob 664 is used for sheathing and unsheathing head110. Rigid coupling 666 is rigidly attached to length knob 664 and tothe sheath so that moving length knob 664 moves rigid coupling 666,which in turn moves the sheath. Sheath 668 is rigidly attached to rigidcoupling 666 so that when length knob 662 moves, sheath 668 moves in thesame direction sheathing or unsheathing head 110.

FIG. 6C shows a blowup of a portion of FIG. 6B.

FIG. 7 shows an overhead view of an embodiment of the outside of ahandpiece 700 used in an embodiment of a hollow body ablation apparatusfor methods of ablation of hollow body organs. The handpiece 700includes an aspirator tube 733, a fluid removal connector 735, anelectrical cord 755, an electrical plug in 760, a length adjustment knob782, a length adjustment groove 783, a width adjustment knob 784, awidth adjustment groove 785, width icon 786, length icon 788, widthscale 790, and length scale 792. In other embodiments the handpiece 700may not have all of the elements or features listed and/or may haveother elements or features instead of or in addition to those listed.

Handpiece 700 may include a shell constructed of a material that allowsfor sterilization. The shell functions to enclose the various parts ofthe hollow body ablation device, including but not limited to, thelevers and push/pull wires necessary to allow change in shape of thedevice, an aspirator tube, wires for attachment to the electrodes toallow RF energy, and a sheath to allow for covering the head of theablation device during insertion into the hollow body organ. Shell 602(FIG. 6A) may be sued as the shell of handpiece 700.

Handpiece 700 may be connected to a controller system (similar tocontroller system 104), which may include an algorithm that allows forthe control of the alternating current (AC) and can be capable ofapplying different patterns of alternating the polarities of thedifferent electrodes of an ablation apparatus. The frequency, voltage,and/or current may be adjusted to fit the cavity dimensions, and can beused to determine overall therapeutic energy doses, and/or determineother settings such as power, duration (the amount of time) ofapplication of the electric field, etc. The controller is discussed inmore detail in conjunction with reference to FIG. 2.

The aspirator tube 733 functions to remove fluid and/or gases from thehollow body organ before, during and after the ablation procedures. Theaspirator tube 733 can be inserted through the shell 702 of thehandpiece 700 and can be snaked up through an attachment tube 710.

The fluid removal connector 735, functions to attach the aspirator tube733 to the reservoir and/or pump.

The electrical cord 755, allows for attachment to the controller system704. The electrical cord 755 and is attached via wires to each electrodeon the head of the hollow body ablation device. The wires can beinserted through the connector tube 710 to the electrodes. The wires canbe connected via the electrical cord to the controller 704.

The electrical plug in 760, allows attachment of the wires within theelectrical cord 755 to the controller system 704. The wires can each beseparately controlled by allowing for separate pins within the plug.Thus, in some embodiments there are the same number of pins in the plugas there are electrodes.

The length adjustment knob 782 may be an embodiment of length knob 664,is attached to the sheath and functions to move the sheath up and overthe head and/or to pull the two sides of the head together to form atube for insertion through an opening into a hollow body organ. Thelength adjustment knob 782 can be rotated to lock the knob in place.

The length adjustment groove 783, allows slideable movement of the knob782 to choose the amount of lengthening or shortening. When the lengthadjustment is at the proximal end, the head is completely collapsed andthe sheath partially or completely covers the head of the device.

The width adjustment knob 784 may be an embodiment of width knob 662,and is attached to levers within the handpiece that effect movement ofpush/pull wires attached to the head to pull each side of the head intoor out of the sheath. Alternatively, the width adjustment knob 748 canmove the distal electrodes into or out of an insulated tube next to theelectrodes on the side of the head. The width adjustment knob 784 can berotated to lock the knob in place.

The width adjustment groove 785 may be an embodiment of slot 612 and mayallow slideable movement of the adjustment knob right and left toincrease or decrease the width, particularly the width of the distal endof the head.

As shown in FIG. 7, information can be provided on the outside of thehandpiece to help the user use the device. The user can be provided withvalues to show the amount of widening or lengthening of the head. Otherinformation can include symbols (e.g., + or −) indicating widening orshortening. Further symbols such as carrots can be used to indicatewidening and/or shortening. Arrows can be included to indicate thedirection of movement of knobs and/or sliding.

Specifically, in an embodiment, width icon 786 indicates to the userthat width knob 784 adjusts the width of the head. In an embodimentlength icon includes an image of the head with arrows indicating thedirection of expansion and contraction, which is along the width of thehead at the top of the head. In other embodiments, another icon may beused. Length icon 788 indicates to the user that length knob 782 adjuststhe length of the head. In an embodiment the length icon includes animage of the head with arrows indicating the direction of expansion andcontraction, which is along the length of the head at the side of thehead. In other embodiments, another icon may be used. Width scale 790indicates the width of the head. Once the user places the head into thecavity and adjusts the head an appropriate amount by sliding width knob784 the position of the knob on width scale 790 indicates how wide thehead has been opened. The reading on width scale 790 of where width knob786 is located may be entered into the controller, for determining thevoltage setting for the ablation. Length scale 792 indicates the lengthof the head. Once the user places the head into the cavity and adjuststhe head an appropriate amount by sliding length knob 782, the positionof the length knob 782 on length scale 792 indicates how long the headhas been opened. The reading on length scale 792 of where length knob784 is located may be entered into the controller, for determining thevoltage setting for the ablation. Once the width and length settings areentered based on the locations of length knob 782 and width knob 784,the controller automatically determines an appropriate power output formodes 1 and 2 at with to ablate the cavity of interest.

FIG. 8A shows a drawing of an embodiment of the fluid removal system 800used in an embodiment of a hollow body ablation apparatus for methods ofablation of hollow body organs. The fluid removal system 800 includes apump 810, a reservoir 814, an activated carbon filter 820, filter media822, filter media 824, a secondary filter 830, and aspirator tube 833.In other embodiments the fluid removal apparatus 800 may not have all ofthe elements or features listed and/or may have other elements orfeatures instead of or in addition to those listed.

The pump 810 can be any appropriate pump known in the art that iscapable of pulling fluid and/or gases from the hollow body organ andinto a reservoir during a procedure. The pump 810 can be attached to areservoir and separated from the reservoir by filters to ensure thatnone of the fluid and/or gases end up in the pump and/or thatnon-sterile air does not come in contact with the hollow body organ. Insome embodiments the pump and/or reservoir includes a sterile seal.

The reservoir 814 can be any type of reservoir 814 that can be attachedto a pump 810 to allow removal of fluids and/or gases from a hollow bodyorgan into a holding area. In some embodiments, the reservoir iscomposed of a material that allows for sterilization. In someembodiments, the reservoir includes an activated carbon filter 820and/or fluid separator 823. In an embodiment, a first layer of filtermedia 822 is followed by the layer of activated carbon 820, followed bya second layer of filter media 824.

The reservoir 814 can include an activated carbon filter 820 thatfunctions to remove particulates before they come in contact with thepump. “Activated Carbon”, also called activated charcoal or activatedcoal is a form of carbon that has been processed to make it extremelyporous and thus to have a very large surface area available foradsorption. The activated carbon filter can be separated from thereservoir by a fluid separator. The reservoir 814 can also include oneor more layers of filter media meant to trap large molecules of fluid orvapor, prior to adsorption by the activated carbon material.

The fluid separator 823 can be any type of porous membrane, sieve orscreen that allows for the passage of air or gases but does not allowfor the passage of fluid or vapor.

The secondary filter 830 can be any type of filter that allows for thepassage of air or gases but does not allow for the passage of fluid,vapor or small particles into the pump. The aspirator tube 833 can allowfor the passage of fluids and/or gases through a tube to a reservoir.The aspirator tube 833 can be attached to a hollow body ablation deviceand can be inserted into a hollow body organ during an ablationprocedure. The aspirator tube 833 can act to remove fluid and/or gasesfrom the organ during the procedure.

FIG. 8B shows another view of the fluid removal device.

Methods of Hollow Body Organ Ablation

FIG. 9 shows a flow chart of an embodiment of method 900 in which ahollow body ablation apparatus (see 100 in FIG. 1A, for example) is usedin a method of hollow body organ ablation.

Advantages of methods of using embodiments of the ablation devicesinclude the ability to reduce the overall profile and size of the deviceto allow for minimally invasive access, to be able to better conform toorgans with distorted cavity shapes, and to reduce the overall cost ofmanufacturing such devices. Ablation is defined as removal or excision.Ablation of the interior lining of a body organ is a procedure whichinvolves heating the organ lining to temperatures which destroy thecells of the lining or coagulate tissue proteins for hemostasis.

Embodiments of ablation apparatus 100 may be used in cases where thehollow body cavity is more of a potential space (e.g., it is a hollowbody cavity that might normally collapse down upon itself unless heldopen by some means). A good example of such a hollow body cavity wouldbe the female human uterus. The uterine cavity is normally a smalltriangular shaped cavity with an entrance at the cervix. The cavity isbasically flat, like an envelope, and is open only when filled with somematerial or possibly pressurized. Since the cavity is essentially flat,the anterior and posterior inner surfaces may or may not be in eitherpartial or direct contact with each other, and a well defined perimeterexists. Whether the anterior and posterior surfaces are in contact witheach other or not, the ablation is still effective and complete.

The methods involve inserting an ablation apparatus into a hollow bodyorgan thru an aperture and ablating the interior lining of the organ.

In step 902 an ablation device such as those described in FIGS. 1-6 isinserted into a hollow body organ. The methods can be used for anyhollow body organ, including but not limited to, a uterus, and a gallbladder. The device is inserted in the collapsed position to allowinsertion through a small aperture into the organ. The efficient packingof right and left halves of the head of the hollow body ablation devicewhen collapsed (folded up) prior to deployment, reduces the overalldimensions of the device for either insertion through a natural orifice,or through an incision. Reducing the size during deployment can beimportant for minimizing trauma to the patient or to reduce anesthesiarequirements to control pain during insertion.

In step 904, the device is adjusted to fit the perimeter of the organ. Aperimeter can be thought of as the length of the outline of a shape. Forexample, the size of a uterus can vary from patient to patient, but hasan approximately triangular shape. Thus, the device can be adjusted tochange the size of the triangular area to fit the shape and/or size of aparticular uterus.

In step 906 the power controller is turned on, and the dimension of theregion being ablated is input into the controller (the controller may beturned on earlier, but the power applied, algorithm chosen is based onthe dimensions and/or characteristics of the cavity). In step 908 analgorithm, the amount of power, and duration of time that is power isapplied, is automatically chosen for a particular organ, based on theorgan, size, for example, based on a lookup table (e.g., according tolookup table 216). In some embodiments, the algorithm decides the typeand amount of alternating current (AC) applied to the electrodes. Thealgorithm may include a determination of the frequency. In someembodiments, the amount and power are applied differently to differentpairs of electrodes. Examples of some algorithms that can be used can befound in the description of FIG. 1D. In some embodiments steps 906 and908 occur simultaneously. In some embodiments, the treatment algorithmmay be read from a lookup table stored in a storage means within theablation device, for example within an EEPROM, compact disk,microprocessor ROM, flash disk or other type of storage media or medium.

In some embodiments, in step 910, mode 1 is implemented (see FIG. 1D fora description of mode 1). A first amount of power is applied for a givenperiod of time to a first region of the organ. The power may be appliedby automatically applying a voltage, automatically measuring thecurrent, and then automatically adjusting the voltage until the poweroutput is at the desired level. In an embodiment, the process of findingthe power level may be iterative.

In step 912, mode 2 is implemented (see FIG. 1D for a description ofmode 2). A second amount of power that is different (e.g. lower) thanthe amount of power applied in step 910 is applied for a second periodof time (e.g., a shorter period of time) to a second region of the organ(e.g., a region having a smaller distance between the walls at theperimeter of the organ. As in step 912, the power may be applied byautomatically applying a voltage, automatically measuring the current,and then automatically adjusting the voltage until the power output isat the desired level. During steps 910 and 912, the amount of power usedfor the method can be from about 20 to about 100 W, including about 30,40, 50, 60, 70, 80, and 90 watts. In some embodiments, the amount ofpower is between about 40 and about 50 W. The power can be left on for atime of between about 50 and about 300 seconds, including but notlimited to, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 105, 110, 115, 120,125, 130, 135, 140, 145, 150, 155, 160, 165, 170, 175, 180, 185, 190,195, 200, 205, 210, 215, 220, 225, 230, 235, 240, 245, 250, 255, 260,265, 270, 275, 280, 285, 290, 295 and all integers in between, dependingon the organ an the dimensions of the organ. In some embodiments thepower is left on for a time of between about 100 and about 150 seconds,depending on the organ the dimensions of the organ.

In an embodiment, each of the steps of method 900 is a distinct step. Inanother embodiment, although depicted as distinct steps in FIG. 9, step902-912 may not be distinct steps. In other embodiments, method 900 maynot have all of the above steps and/or may have other steps in additionto or instead of those listed above. The steps of method 900 may beperformed in another order. Subsets of the steps listed above as part ofmethod 900 may be used to form their own method.

Methods of Making Hollow Body Organ Ablation Devices

FIG. 10 shows a flow chart of an embodiment of method 1000 in which ahollow body ablation apparatus (see 100 in FIG. 1A, for example) isconfigured.

In step 1005 the ablation device (see 101 in FIG. 1) is assembled. Anembodiment of step 1005 is discussed in conjunction with FIG. 11.

In step 1010, a fluid removal device is attached to the ablation device(see 101 in FIG. 1). The fluid removal device can include a tube thatcan be snaked up through the handle and/or through the device to leavean opening within or next to the device. The tube can be attached to areservoir and/or pump.

In step 1020 a controller is attached to the ablation device. Thecontroller can also be attached to an electrical outlet and can controlthe amount of power the electrodes deliver to the tissue (by controllingthe voltage applied to the electrodes) and/or the algorithm to be used.Thus, attaching the controller may include attaching the controller tothe wires that are attached to the electrodes through a connector. Theconnector can be a wire with a plug having at least 6 pins, one pin foreach electrode on head 110. Optionally, there may be an additional twoor more pins, and a controller may be attached to the additional pins.Using the additional pins, the controller may also be used for recordinginformation about the ablation, such as the power, and duration of timeof each mode applied.

In an embodiment, each of the steps of method 1000 is a distinct step.In another embodiment, although depicted as distinct steps in FIG. 10,step 1002-1020 may not be distinct steps. In other embodiments, method1000 may not have all of the above steps and/or may have other steps inaddition to or instead of those listed above. The steps of method 1000may be performed in another order. Subsets of the steps listed above aspart of method 1000 may be used to form their own method.

FIG. 11 shows a flow chart of an embodiment of method 1100 in which anablation device (see 101 in FIG. 1A, for example) is configured. Method1100 is an embodiment of step 1005 in FIG. 10.

In step 1105 a handpiece is assembled to include knobs for adjustment ofthe length and width of the device. The knobs can be attached to thepush-wires to control the collapsing of the electrode apparatus into thesheath. In some embodiments, within the handpiece the knobs are attachedto levers which are attached to push and pull wires and moving the knobsmoves the push and pull wires as needed to change the width and lengthof the device. The knobs can move the levers by sliding the levers alonga groove (e.g., in a side to side direction to change the width and/orin a back to front direction to change the length). In some embodiment,the knobs can be attached to a lever that is attached to a push or pullwire that moves the sheath up or down as desired for insertion of thedevice.

Within the handpiece are wires connecting electrodes to the power sourceand/or controller. In some embodiments, there are the same number ofwires as electrodes. The wires can be connected to the controller via apower cord and plug. Also included within the handpiece is an aspiratortube to allow removal of fluid during the procedure.

In step 1110 a sheath is assembled by attaching the sheath to thehandpiece and to a width and/or length adjustment knob on the handpiece.The adjustment knob can be attached to a push or pull wire that pushesor pulls the sheath over the device or back from the device depending onthe way the knob is turned or moved.

In step 1120 the head (e.g., the electrode apparatus) is assembled to bethe approximate shape of the hollow body organ (e.g., triangularlyshaped, a parallelogram or oval). The head has electrodes on the baseand the sides of the device. Each side of the device is attached so thatthe sheath can be moved to cover the electrodes. The electrodes arechosen to allow movement into and out of the sheath. The electrodes arechosen to allow movement of the device from a triangular shape (orparallelogram) to two parallel sides covered by the sheath whencollapsed. The electrodes can include moveable electrodes and rigidelectrodes. The electrodes can include D-shaped electrodes to allow thedevice to be collapsible. The electrodes can be separated by insulatorsto keep the electrodes from touching.

In step 1140 the electrode apparatus, sheath and handpiece are attachedso that a user can manipulate the device to collapse and cover theelectrode apparatus (e.g., with the sheath) so that when inserted thedevice can fit through a small aperture. This step also allows the userto manipulate the length and width of the device to fit the size of thehollow body organ.

In an embodiment, each of the steps of method 1100 is a distinct step.In another embodiment, although depicted as distinct steps in FIG. 11,step 1105-1140 may not be distinct steps. In other embodiments, method1100 may not have all of the above steps and/or may have other steps inaddition to or instead of those listed above. The steps of method 1100may be performed in another order. Subsets of the steps listed above aspart of method 1100 may be used to form their own method.

EXAMPLES

In the following examples, embodiments of the ablation devices were usedto treat a test specimen (a beef steak) and the width, length and depthof treating was measured. Beef steak was used to approximate the hollowbody organ—“a meat cavity.” Using the methods and devices herein inwhich radio frequency electrodes were arranged in a pattern that madecontact with the surface area of the beef steak, energizing theelectrodes resulted in treatment of a much larger area than wasspecifically contacted by the electrodes. When used in a hollow bodyorgan, this would result in a complete ablation of the lining of thebody cavity, even though the electrodes only make contact with thesurface area of the organ in proximity to the perimeter. This hasnumerous advantages over the prior art in which devices to performcomplete ablation of a hollow body cavity required that radio frequencyelectrodes cover all or substantially all of the surface area to beablated, rather than just a portion of the surface area in closeproximity to the perimeter of the organ.

Example 1 Test Treatment of a Beef Steak with the Ablation Device Shownin FIG. 1

Example 1 describes the results from a test for the endometrial ablationdevice shown in FIG. 1A. The tests assumed a uterus size of 4.5 cm wideby 6.5 cm long. Thus, the device was configured to have a 4.5 cm longbase and 6.5 cm long sides. All tests were performed using two slices ofbeef in a “meat cavity”.

As shown in FIGS. 12 and 13, the device was configured with sixelectrode segments as follows: The distal electrodes (on the base) were0.077″ diameter, stainless steel extension springs. The middleelectrodes were stainless steel D-tubing created from 3.75 mm OD tubing(9 GA). The D-length was 2.60 mm and the D-width was 4.55 mm. Theproximal electrodes were stainless steel D-tubing (as above) with slotscut in the round portion of the D to allow for flexibility in only oneplane. The goal of the test was to find the optimum power and timesettings to effectively treat the tissue. So, a number of tests wereperformed varying the amount of power (watts), the amount of time(seconds) and using more than one mode as follows:

Test 1. FIG. 12 shows a front elevation view of the method of testing ahollow body ablation apparatus in which RF energy was applied at 50 Wfor 120 seconds for mode 1. In FIG. 13 the RF had not yet been appliedto the electrodes, but the head of the device was fully opened. FIG. 12shows a front elevation view of the method of testing a hollow bodyablation apparatus-after applying mode 1 at 50 Watts for 120 seconds.FIG. 12 shows that the electrodes affected an area wider than the widthof the electrodes. In fact, the whole area defined by the head of thedevice was affected including up to 10 mm outside of the electrodes.Thus, as judged by the widely affected area, the algorithm does morethan just apply current.

FIG. 13 shows a front elevation view of a method of testing a hollowbody ablation apparatus-post-treatment without the device. FIG. 13 showsthat the treatment affected the area within the devices electrodes andalso an area of between 3 and 10 mm outside of the area that theelectrodes touched. The amount of heating was surprisingly even,although there was more heating directly under the electrodes.

The depth of the treatment was analyzed by cutting the steak through thecenterline and sides of the affected area and measuring the depth. Thesteak was affected at a depth of about 4 to 10 mm at the centerline ofthe treatment as well as directly under the electrodes. FIG. 13 alsoshows test points D1-D5 at which the depth of ablation is measured. Thetest area is cut along the lines connecting points D1-D5 so that thedepth of heating can be measured.

Other tests were as follows:

Test 2: Mode 1 was 40 watts for 150 seconds; Mode 2 was 30 watts for 30seconds. This method showed an equal effectiveness to the first test.

Test 3: Mode 1 was 50 watts for 113 seconds. This method showed an equaleffectiveness to the first test.

Test 4: Mode 1 was 40 watts for 150 seconds; Mode 2 was 30 watts for 30seconds. This method showed an equal effectiveness to the first test.

The smaller overall surface area of the smaller round springs resultedin a higher energy density at similar powers. To get the desiredresults, settings of 40 W for 150 seconds and 30 W for 30 seconds wasrequired. However, higher powers resulted in charring and therefore lesseffective treatment time.

Table 2 provides the results for 20 different treatments using differentwidths and lengths, and a variety of modes. In Tables 2A and 2B, FIGS.16 and 17, depth is provided for electrodes D1-D6. The numbering of theelectrodes is as shown in FIG. 1A2. However, in all cases, the depth oftreatment as shown resulted in a good result. The test results wereunexpectedly good in that the periphery (which is close to or in contactwith the electrodes) is not charred, the entire cavity is heated(including the central area in the center of the opening of the head110), and the depth of heating is shallow enough so as not to heat themyometrium or serosal layer of the uterus.

Each embodiment disclosed herein may be used or otherwise combined withany of the other embodiments disclosed. Any element of any embodimentmay be used in any embodiment.

Although the invention has been described with reference to specificembodiments, it will be understood by those skilled in the art thatvarious changes may be made and equivalents may be substituted forelements thereof without departing from the true spirit and scope of theinvention. In addition, modifications may be made without departing fromthe essential teachings of the invention.

1. A hollow body ablation apparatus, comprising: a head having at leastthree electrodes, at least one insulator and a sheath, said headcomprising an elongate member having sides and a base, said sides andbase being flexible; a sheath; a handpiece connected to the headcomprising width and length adjustments that can adjust the width andlength of the sides and base of the head, wherein said head can becollapsed into said sheath using the width and/or length adjustments. 2.The hollow body ablation apparatus of claim 1, wherein the sides andbase are flexible due to the use of flexible electrodes.
 3. The hollowbody ablation apparatus of claim 1, wherein the sides and base areflexible due to the use of flexible insulators.
 4. The hollow bodyablation apparatus of claim 1, wherein at least one of the electrodes isa coil electrode.
 5. The hollow body ablation apparatus of claim 1,wherein at least one of the electrodes is a tube electrode, the tubehaving a cross sectional shape that is noncircular.
 6. The hollow bodyablation apparatus of claim 1, wherein at least one of the electrodes isa slotted D-tube electrode.
 7. The hollow body ablation apparatus ofclaim 1, wherein at least one of the electrodes is a bead-chainelectrode.
 8. The hollow body ablation apparatus of claim 1, wherein atleast one of the electrodes is an accordion electrode.
 9. The hollowbody ablation apparatus of claim 1, wherein at least one of theelectrodes is a braided metallic wire electrode.
 10. The hollow bodyablation apparatus of claim 1, wherein at least one of the electrodes isa telescopic electrode.
 11. The hollow body ablation apparatus of claim1, wherein at least one of the insulators is a flexible insulator. 12.The hollow body ablation apparatus of claim 1, wherein the diameter ofthe sheath is between about 4 and 6.5 mm.
 13. A hollow body ablationapparatus, comprising: at least one D-type electrode, said D-tubeelectrode comprising a tubular electrode having a D shape such that theinnermost semicircular region is removed to form a tubular electrodewith a “D” cross section.
 14. A hollow body ablation apparatus,comprising: a head having a triangular shape with at least threeelectrodes, said at least three electrodes at the perimeter of thetriangular shape, at least one of the electrodes is a preloaded spring,which tends to push the head into the triangular shape, and noelectrodes are located within an inner edge of the perimeter formed bythe at least three electrodes.
 15. A hollow body ablation apparatus,comprising: a head having a distal end and two sides, comprising atleast six electrodes, wherein two electrodes are located on the distalend, and four electrodes are located on the two sides; and a handpiece,wherein each of said electrodes can be separately activated.
 15. Thehollow body ablation apparatus of claim 15, wherein the distalelectrodes on the distal end and the two sides can be activatedseparately from the proximal electrodes on the side.
 16. The hollow bodyablation apparatus of claim 15, wherein the activation involves applyingan AC or RF energy delivery mode.
 17. A method for ablating a hollowbody organ, comprising: (a) providing an ablation device including ahead having at least one electrode, at least one insulator and a sheath,said head comprising an elongate member having sides and a base; ahandpiece connected to the head comprising width and length adjustmentsthat can adjust the width and length of the sides and base of the head,wherein said head can be collapsed into said sheath using the widthand/or length adjustments; (b) positioning the head in contact withtissue in the perimeter of the hollow body organ; (c) delivering RFenergy through the electrodes to the tissue, wherein the RF energy isdelivered by applying a first amount of power to a first portion of thehollow body organ and applying a second amount of power that is lowerthan the first amount of power to a second portion of the hollow bodyorgan.